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arXiv · 1910.06921

Time-Reversal Invariant Topological Superconductivity in Planar Josephson Bijunction

Yanick Volpez·Daniel Loss·Jelena Klinovaja
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Abstract

We consider a Josephson bijunction consisting of a thin $SIS$ $π$-Josephson junction sandwiched between two-dimensional semiconducting layers with strong Rashba spin-orbit interaction. Each of these layers forms an $SNS$ junction due to proximity-induced superconductivity. The $SIS$ junction is assumed to be thin enough such that the two Rashba layers are tunnel-coupled. We show that, by tuning external gates, this system can be controllably brought into a time-reversal invariant topological superconducting phase with a Kramers pair of Majorana bound states being localized at the end of the normal region for a large parameter phase space. In particular, in the strong spin-orbit interaction limit, the topological phase can be accessed already in the regime of small tunneling amplitudes.

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Yanick Volpez, Daniel Loss, Jelena Klinovaja. 2019-10-15. Time-Reversal Invariant Topological Superconductivity in Planar Josephson Bijunction. https://doi.org/10.1103/physrevresearch.2.023415

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